Drier.



No. 708,602. Patented Sept. 9, I902.

' r A. T. WELCH.

I DRIER.

(Applicutian filed May 28. 1897.]

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No. 708,602. Patented Sept. 9, I902.

A. T. WELCH.

D R l E R.

(Application filed May 28. 1897.

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Patented- Sept. 9, I902.

A. T. WELCH.

D B l E B.

(Application filed May 28. 1897.1

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PATENT @nrroa BALTIMORE, MARYLAND.

DRIER.

To all whom it may concern:

Be it known that I, ABRAHAM T. WELCH, a citizen of' the United States,residing at Baltimore, in the State of Maryland, have invented certainnew and useful Improvements in Driers; and I do hereby declare thefollowing to be a full, clear, and exact description of the invention,such as will enable others skilled in the art to which it appertains tomake and use the same.

This invention relates to driers.

The objects are rapidly and evenly to dry organic or other substances tothe desired degree and at the same time to effect their separation ordivision into parts or particles of the requisite or desired fineness;furthermore, to avoid Waste of heat by utilizing the same in such mannerthat the moist substance or substances will be subjected to heat of thehighest temperature on entering the drier and to heat of aprogressive]y-decreasing temperature toward the discharge end,

and, finally, to regulate the heat in the drier in accordance with theamount of drying to be accomplished.

In my invention I employ arotating drum provided on its interior with anumber of shelves sharpened at their edges to form material andpreventing any balling or lumping thereof. The shelves in this instanceincrease in number from the feed end to the discharge end of thedrumthat is to say, at the feed end there will be the fewest number ofthese shelves and at the discharge end the greatest number. Thisarrangement is adopted in order that the material when it first entersthe drum will be picked up in large masses and be subjected to thegreatest heat, and as it is moved or worked through to the discharge endof the drum the increased number of these shelves or knives will operateto break up and finallydivide the material being desiccated. The feedend of the drum is closed by a head, (the plane of which is at rightangles to the axis of the cylinder,) through which opens thecombustion-chamatent No. 708,602, dated September 9, 1902.

Serial No. 638,659. (No model.)

ber, of smaller diameter than the drum. Through this chamber is blown astream of flame at a high temperature and in a direction substantiallyparallel with the axis of the drum. Thecombustion-chamberhasitssidessubstantially parallel with the axis of the drum, thus causing the hotflame, gas, or air to be-projected into the drum centrally withclose upto the feed end. If the combustionchamber presented a material wideningin the end toward the drum, the hot flame, gas, or air would spread outand fill the crosssection of the drum where it entered it and materiallyinterfere with the proper action of the drier. Opening into the drumabove the combustion chamber is the hopper through which the material tobe dried is fed into the drum. The discharge end of the drum is of aslarge a diameter as any other part of the drum and afiords a free andunobstructed discharge. The rear or discharge end of the drum issurrounded by a dust-arrester consisting of a casing or hood constructedof perforated material and terminating at its lower side in a chute ordischarge, the drum being provided witha brush adapted to keep thetop,sides,and ends of the arrester clean and free from any accumulationof dust. This arresterand also the rear portion of the drum may behoused in a dustroom provided with a stack and a suitable damper, andalso suitable inlet-openings through which atmospheric air may pass tothe roof of the dust-room to cool or chill any dust which may escapefrom the dust-arrester and cause it to settle to permit of its beingcollected.

The apparatus-Which is the subject-matter of this application isdesigned to carry into vided out of this application and made thesubject-matter of a divisional application filed by me June 7,190l,Serial No. 63,658.

The drum being set in rotation and the flame adjusted, the goods to bedried are fed into the drum through the hopper at a suitable rate. Theyfall, therefore, in their wettest condition through or near the hottestpart of the flame. On account of the position and shape of thecombustion-chamber this part of the d rum is not filled by the flame,

effect a process of drying which has been diout filling the Wholecross-section of the drum and the goods fall through the flame to acooler part of the drum without the temperature being raised to thepoint of scorching, the time during which the material is eX- posed tothe direct action of the flame and the time during which it is notexposed to the direct action of the flame bearing such a relation to oneanother that the material will not be raised in temperature to theignitionpoint. The pieces are more or less broken up by falling on thesharpened edges of the shelves, which as the drum rotates pick them upand drop them again through or near the flame. The goods are thusgradually dried and by means shortly to be described are moved towardthe discharge end of the drum, being subjected progressively to a lowerdegree of heat, and are finally discharged from the drum as dry as maybe desired. The pro gression ofthegoodsis caused by fourmeans first, bythe force of the blast of flame or hot air; second, by the rate of feed,forthe greater this rate the greater will be the piling up of the goodsat the feed end of the drum and the greater the slope of their surfacetoward the discharge end, so that every time a piece is raised by theshelves and dropped it will tend to roll a short distance toward thedischarge end; third, by the slope of the drum,which will act as in thelast case; fourth, by the rate of rotation of the drum, which willincrease the number of times per minute each piece is dropped, and henceits speed of progression to the discharge end. Of these the first twoare found to besufficient to control the proper action of the drier. Thefirst is so important in its action that it will be especiallydescribed.

Of the various materials usually treated in a drier the larger andheavier usually contain the greater amount of moisture, and as the heatreceived by a particle in a given time depends on the surface, whereasthe amount of moisture to be evaporated depends on the volume, we seethat it takes a longer time to dry the larger and heavier'pieces than itdoes to dry the smaller and lighter ones. Now the larger and heavier thepieces the less will they be deviated by the force of the blast as theyfall through or near the flame and the more slowly, therefore, will theyprogress toward the discharge end of the drum. As the pieces becomedrier and more broken up they become lighter and are more affected bythe blast of the flame. This method of discharge is of extremeimportance, as it causes the rapid discharge of those pieces which arerapidly dried and allows the pieces requiring a longer time to remainlonger in the drier. Indeed, it regulates the discharge of the variouspieces as they reach the proper degree of dryness so well that goodscontaining pieces of very different sizes and very different natures maybe put into the drier at the same time and all be discharged properlydried. The small section of the blast at the feed end causes great forceof blast and drives small light objects rapidly out of the drum,preventing them from being scorched or burned. The force with whichpieces of the goods are driven along the drum depends also on thestrength and temperature of the blast. By contact with the wet goods andotherwise the temperature of the blast is greatly reduced and thedensity of the gases of combustion greatly increased, with acorresponding decrease in the velocity of the individual gas molecules.This velocity is also diminished by the fact that in the case of somefuels the gases of combustion at the same temperature occupy a smallervolume than the gas and air before combustion. Therefore the drivingpower of the blast diminishes progressively and rapidly from the feedend to the discharge end of the drum. Not only so, but the wetter thegoods the greater the reduction of the temperature of the blast andtherefore the greater the reduction of its driving power. Therefore,other conditions being equal, the Wetter the goods the more slowly willthey progress along the drum, and consequently the longer will theyremain in the drum and be subjected to the drying action of the blast.It is important that the direction of the blast should be substantiallyparallel to the axis of the cylinder for the purpose of causing thegoods to progress through the cylinder or to drive them, if lightenough, out of the cylinder.

An important part of my invention is the use of the flame and that at anextremely high temperature. It is evident that the higher thetemperature the more rapid the drying. Moreover, there is always someheat carried off by the hot air issuing from the discharge end of thedrum, and therefore the smaller the quantity of air discharging inproportion to the amount of heat introduced into the feed end of thedrum the greater the economy. This proportion is reduced byincreasingthe temperature of the feed end. The use of the flame in the drum is farmore economical than the use of this same flame to heat air and then todrive the air under pressure into the cylinder. Hot air forced into thecylinder under pressure would lose heat on expansion and could not,therefore, have the high temperature with which it started. Consequentlygreat waste follows; but the flame produces the high temperature whenthe gas has lost its high pressure. Consequently the waste does notoccur. Although I do not claim as my invention the use of a hightemperature, I do claim that the practical use of the flame for dryinggoods without injuring them has never before been accomplished and thatits use in this connection is so novel and results in such'enormouseconomy and rapidity that it constitutes a very important invention. Thevery high temperature of the blast at the feed end of the drum causes avery low density, and hence a very small specific heat per unit ofvolume. Therefore when it acts on the wet goods and heats them andevaporates the moisture its temperature is enormously reduced. In fact,

we find the temperature 3,000 or 4,000 at the feed end and less than 200at the discharge end. This enormous drop in temperature greatlydiminishes the power of the air to hold the evaporated water insolution, and as the goods are always colder than the air in the drumthere is danger that the moisture taken up at the feed end may beredeposited on the goods near the discharge end, and thus frustrate thewhole purpose of the drier. The success of the operation thereforerequires that at no point of the drum shall the hot air, gas, or flamebe so overcharged with vapor that moisture will be redeposited or, whatis equivalent, that at every point of the drum the hot air, gas, orflame shall always be absorbing moisture from the goods. There is thus aprogressive and continuous drying and heating of the goods. The rate atwhich the hot air, gas, or flame can absorb moisture from the goods andheat them may be called its dryingandheatingpower. Forconvenience weshallcallit merely the power. It is greatest at the feed end, where thetemperature is high and where the amount of absorbed vapor is small, andit continuously diminishes toward the discharge end, where thetemperature isrelatively low and the amount of absorbed vapor high. Thispower can always be kept largeby keeping up the temperature;

= but there is danger then that the goods be scorched and even that theycatch on fire. At the feed end the very moist goods drop through anintensely-hot flame, but remain in it a very short time. The heat of theflame is used to warm them up somewhat and to evaporate their moisture;but they pass out of the flame into a cooler region before they can besufficiently heated to be burned. Farther down the drum the hot blastspreads until it fills the whole cross-section of the drum, and thegoods, therefore, are constantly subjected to its drying and heatingpower. If the goods are moist enough, the steady evaporation of theirmoisture prevents them from becoming too highly heated; but if even on.the surface they become too dry they will quickly be heated toahightemperature and be burned. The rate at which energy is being absorbed inevaporating the moisture and heating the goods may be spoken of as therate of doing useful work or, for convenience, merely the work. If thepower is too great in comparison with the amount of moisture in thegoods, the goods will be highly heated and burned. (This will not be sowhen the temperature of the hot air or gas is so low that it could notburn the goods under any circumstances; but then. we should beworking atvery ineflicient and uneconomical temperatures, and this would becommercially impractical.) On the other hand, if the power is too smallin comparison to the work tobe done either the goods will not be driedor moisture may even be rcdeposited on them. It

is evident, therefore, that the power and work must substantiallybalance at all points of the drum. The fact that the power and work arebalanced in all parts of the drier is shown to the operator by the goodscoming out at the discharge end of the drum properly dried, and whenthey do so come out he knows that the power and work are balanced. Ifthe goods come out moist, it shows that there is too much Work for thepower, and therefore either the power must be increased or the amount ofwork diminished. On the other hand, should the goods come out scorchedit shows that the power is too great for the work and either the powermust be decreased or the amount of work increased. In other words, whenthe power and work at all points in the receiver are balanced the goodscome out of the receiver properly dried, and they are not properlydried-that is to say, they are either too moist or scorched-when thepower and work are not balanced. It will be seen, therefore, that whenthe power and work are not balanced the same is shown by the conditionof the goods coming out of the receiver and that they may be broughtinto balance by varying the amount of heat entering the drum or theamount of goods fed to the drum.

Further and more specific details of construction will be hereinafterdescribed and claimed.

In the accompanying drawings, forming part of this specification, and inwhich like letters of reference indicate corresponding parts, I haveillustrated a form of embodiment of my invention, although it is to beunderstood that other forms of embodiment thereof may be employedwithout departing from the spirit of the same, and in these drawingsFigure l is a view in sectional elevation displaying a drier embodyingthe essential features of my invention. Fig. 2 is a transversesectionalview taken on the lines 2 2, Fig. 1, showing more particularlythe feed-hopper and the feed or disintegrating drum therein. Fig. 3 is asimilar view taken on the line 3 3, Fig. 1, showing more particularlythe arrangement of the shelves or knives on the inside of the drum. Fig.4: is a similar view taken on the lineat, Fig. 1, showing the perforatedplate for regulating the supply of air to the burner; and Fig. 5 is aView in elevation of a modified form of drum. Fig. 6 shows the sameparts as Fig. 1 with the addition of the cylinder shown in Fig. 5.

Referring to the drawings, A designates the drum, which maybe made ofanysuitable material, preferably of iron, having its inlet or feed endclosed by a hood or plate a, the same being held in position against thedrum by braces a, and its eXit or discharge end open. The drum is shownin this instance supported in an inclined position, with the exit ordischarge end lowest, and is driven by a gearwheel M, on the shaft ofwhich is mounted a "from any suitable source.

pulley a by which power may be transmitted Meshing with the gear a is agear a on the drum. The drum is supported for operative movement upontwo wheels or rollers a and a, the same being engaged by bands (1 and asecured around the drum. The periphery of the roller (1 is smooth; butthe periphery of the roller a is provided with two flanges, betweenwhich the band a works to preventlongitudinal movement of the drum whenthe same is rotated. The rear end of the drum may be incased by ahood ordust-arrester B, consisting of frames or standards I), to which the hoodB is secured, the same being about three-quarters of a circle and openat its bottom, so that the material may escape down a chute b to asuitable receptacle. The top, sides, and one end of the hood areconstructed of any suitable material, such as perforated screens, andare kept free from any accumulation of dust by an L- shaped brush a,carried by the discharge end of the drum. Thus as the drum is revolvedthis brush will scour the sides, top, and end of the hood and clear themeshes or holes thereof from dust. The dust which escapes to the outsideof this hood passes into a dust-room O, in which the rear portion of thedrum may be incased, the room being an ordinary chamber provided with astack 0, which is larger than necessary, to carry off vapors from thedrier, and with a damper 0 The top portion of this room is provided witha series of openings 0 by which atmospheric air can pass to the interiorof the room and chill and settle the dust afterward to be collected.This dust-room with the stack, constitutes a means for relieving thepressure at the dischargeoutlet, and this is effected bythe pull of thestack and by preventing any air which may be stirring in the room wherethe drier is located from affecting the operation of the drier. Ofcourse any other means for effecting this function might be substitutedfor this shown,if found desirable. Secured to the interior of the drumand longitudinal of its length is a series of shelves a the function ofwhich is to agitate, pick up, and drop and separate or divide thematerial as it passes through the drum, and thereby present the materialconstantly to the action of the heat. These shelves progressivelyincrease in number toward the discharge end of the drum-that is to say,at the feed end there will be, say, eight of these shelves a littlefarther on sixteen, and at the discharge end thirty-two, or this numbermay be increased or diminished, as found necessary or desirable. Theshelves are set radially of the drum and are sharpened on their edges,so that as the material is dropped upon their edges they will cut anddivide it. As the material enters the drum in a spray through theintense heat it is in its wettest condition and the shelves will pick itup in masses or bunches and drop it, thereby causing an initialdisintegration and the subjection of the entire area of the material tothe action of the highest heat. As the material works toward thedischarge end of the drum the increased number of these shelves willtend to break up or disintegrate the dried or partially-dried material,so that by the time it has reached the discharge-chute b it will be in afinely-divided state. Any suitable means may be employed for feeding thematerial to the drum, and in this instance I employ a toothed feed anddisintegrating roller a arranged in a hopper a at the inlet or feed endof the drum, the said hopper being provided with knives or projectionsa, coacting with the teeth on the roller to break up and at the sametime force the material to the drum in a spray across the path of theflame, which partially dries it and prevents balling. The opening wherethe material enters the drum is normally closed by a gravity operatingdoor or valve a, which, as will be seen, will allow the material freelyto enter the drum, but will prevent its escape therefrom, and will alsoin a great measure cut off the escape of foul odors or escape of gasesor the entrance of cold air.

Connecting with the hood or plate a is a combustion-chamber D, intowhich enters a pipe 6 from a supply of air under pressure and a pipe J"from a supply of fuel, which may be either gas or oil. In case thelatter is used the chamber 01, surrounding the pipe (2, may be filledwith wool asbestos. The pipe B delivers air some distance ahead of thepipef to prevent extinguishing the flame when the proportion of airunder pressure is large and the flame small. In this instance I haveshown the fuel-supply as coming from acarbureting apparatus F,consisting of a tank f containing oil, in which is arranged a float fdesigned tojdeflect a current of air supplied thereto through a pipe fopening into an airometer or holder G, the latter being supplied withair through pipes h and 7L2 from an air-forcing device H in the natureof a pump or positive blower. ports a safety-valve 713, the lever h ofwhich carries a depending arm 71 arranged in the path of movement of thehood of the air-receiver or airometer, so that when the receiver reachesa predetermined height the arm 7t will be lifted and allow the air beingforced from the pump to escape instead of entering the receiver, therebyestablishing and maintaining a uniform pressure of air and fuel. Boththe pipes e and f are provided with valves c and f respectively, bywhich the supply of air and gas to the combustion-chamber may beregulated at will. The rear portion of the combustion-chamber isprovided with a perforated plate (Z adapted to be moved to open or toclose openings d in the rear plate of the said chamber, whereby toregulate the supply of atmospheric air to the burner. To facilitatelighting the burner, a lighter-pipe f is employed, having one of itsends tapped into the gas-pipe f, as shown in IIO The pipe 71, sup- 1 (1by which the temperature of the chamber may be determined. Thecombustionchamher, with its air and gas pipes, constitutes a compoundinjeetorthat is to say, an injector through which air and gas inpredetermined or regulated quantities maybe supplied to the drum.

The operation of the apparatus is as follows: Air from the receiver Gand gas from the carbureter F are supplied to thecombus.

tion-chamber, and the gasis lighted and burns a red flame and mixes withthe air farther on in the combustion-chamber. As the supply of air tothe carbureter and to the pipe E are from the same source, it followsthat the supply of each is exactly proportionate, the valves 6 and fbeing set with respect to each other. The supply of gas and air ispositively supplied and gravity-controlled, as the holder of theairometer will by its weight operate to supply air under pressure to theburner, so that there will be always a uniform supply of air and gasthereto, thereby avoiding fluctuation in the supply of heat, with acorresponding variation in the desiccating power of the flame or blastof air. The advantage of this arrangement Will be obvious, for it willbe seen that if the valves f and c are set the degree of heat willremain constant without any attention being paid it throughanylengthoftime,provided,of course, the supply of oil is maintained in thecarbureter and the pump H is kept at work. The flame being lighted willbe projected into the dru tn any desired distance, its speed and forcebeing regulated,of course,by the volume of air and fuel admitted to thecombustion-chamber and their pressure in the airometers. The material isnow fed to the hopper e and as it passes into the drum in a spray is metby an intense heat, which will serve rapidly to dry the exterior of thematerial. ,As often as the material drops it is caught by the shelves atand is again lifted and dropped, beingthusintermittentlysnbjected tothefireuntil it has passed beyond it, and as the material approaches thedischarge end of the drum the temperature will gradually decrease. The

heat absorbed by the material will as it passes through the length ofthe drum penetrate to the center of the material, which will then bedried to the desired degree. As before stated, the shelves increase innumber toward the discharge end of the drum, so that the material willbe finely broken up and divided be fore it escapes through the chute W.I have found in practice that moist fish can be thoroughly andeffectively dried by flame without burning and that oystershells may atone operation be calcined by this form of drier.

Other materials-such as hair, tankage, and the like-are effectivelydried by flame without being burned, as the direct contact of the flamewith the material is of such short duration that before the moisture isthoroughlyevaporated from the exterior the m aterial will have passedbeyond the zone of the flame and will therefore be protected fromscorching. In my apparatus the rate at which the fuel is supplied to theburner is automatically controlled. The rate at which the air issupplied is also automatically controlled.

Hence the temperature and volume of the of the apparatus. The settingmay be varied, but when set the temperature and force of blast will beconstant. This constant temperature and force of blast is a veryimportant element in the practical operation of the apparatus, for thereasons that the temperatures employed are so high that unlessconditions in the drier are absolutely under control burning will almostcertainly result. The material to be dried can now be fed to the drum inmeasured quantities of known moisture and known weight. With anapparatus in which the drum has a constant speed, the number andlocation of shelves having been. arranged to suit conditions of dryingdesired and the material to be dried, the strength of the blast, thetemperature, and the volume of flame being constant, the only elementrequiring to be Watched and altered to produce exact conditions is thefeed, and when this is carefully regulated uniform and positive resultscan be obtained.

In my drier, in which the contents of the cylinder is heated by heatapplied inside the cylinder alone, no matter how highly the contents maybe heated the exterior shell of the vessel-that is, the cylinderitselfremains cool, and the effect is that when the hot and dampmaterial falls against the inner surface of the cylinder there is aslight contraction of each portion of the hot material asit strikes thecooler shell, which draws the material away from the cylinder, leavingthe inside of the cylinder constan tly clean.

While I have shown the feed-hopper and feed roller ordisintegrating-drum in this instance as located at the inlet end of theapparatus, it is to be understood that in some instances I may dispensewith the disintegrating apparatus at the inlet end and locate it at thedischarge end of the cylinder. This arrangement will be foundadvantageous where the material is in a very wet or soft and mushycondition, as where garbage or very moist fish is to be dried, and asthis passes through the drum or drier it will form into balls or lumps.These will still contain a high degree of heat when they enter thedisintegrator. at the discharge end of the apparatus and will be finelyground up or divided and then be forced rapidly through the air. Theheat contained in the mass will cause any retained moisture to hebrought to the surface and into contact with the atmospheric air, whichwill rapidly cool and evaporate it.

While I have not shown the means herein, it is to be understood that thematerial fed to the apparatus will be weighed or otherwise measured, sothat the bulk or body of the material fed to the apparatus will beproportionate to the volume of air and heat and speed of travel ofmaterial through the drier. In other words, the feed of air, the feed ofgas, supply or feed of material, and speed of material through theapparatus are all interdependent. The material will drop by gravity intothe receptacle and when picked up by the shelves of the cylinder willdrop by force of gravity and be progressively fed to the flame or blastof air, provided the apparatus rotates uniformly.

In Fig. 5 I have shown a form of drum in which the fine particles ofmaterial may be separated from the coarser particles and be removed fromthe drum when quick drying is required, so asto obviate waste of heatand also injury to the material. To effect this, I employ screens orsieves as sections of the walls of the drum, one of these screens 1being located, preferably, at about the middle of the drum and theother, 1 at the discharge end. By this means all the finer dry materialcan be separated from the coarser damp material, which will be subjectedto a further disintegrating process, consisting in this instance of adisintegrating-drum 2', arranged in a hopper 2' at the discharge end ofthe drum. As will be seen, the discharge end of this hopper curvesupward and outward, so that as the material is thrown out by thedisintegrating-drum 2' it will be scattered out in a sheet, thus toeffect the final drying. This latter step would be advantageous for thereason that it will avoid driving off the contained ammonia in thenearly dry material, as if this fine material were subjected directly tothe action of a too-high degree of heat the result would be that part ofthe ammonia would be driven off and there would be danger of burningsome materials. The operation just described would consist in thesubjection of the goods to the action of fire and subsequently theagitation of the hot partially-dried goods in the presence of air coolerthan that to which the goods were originally exposed. It is essentialthat the temperature used in the second stage of this operation shouldbe less than the temperature used in the first operation for the reasonthat goods which are nearly dry will burn if exposed to as high atemperature as that to which they were originally exposed when verymoist. Another advantage in employing the disintegrating-drum at thedischarge end of the drier is thata platform may be arranged adjacent tothis hopper upon which the material may be thrown by the action of thedisintegrator to allow remaining moisture to escape and also to save thefine and valuable dust, which might otherwise be lost if thoroughlydried in the drier.

Heretofore many attempts have been made to employ flame directly upongoods for the purpose of drying, evaporating, or heating; but theseefforts have always resulted in burning the material, because the timeduring which the materials were exposed to the flame or air and theproper proportion between the power and the work given it to do were notunderstood and regulated in such manner as to secure the beneficialeffects of the flame while preventing it from injuring the goods. Thedifierence between all these attempts and my invention lies in theapplication of the direct or direct-radiant action of a flame to thematerials, regulated in such a way as to balance the power and the work.None of the previous effort-sin this line have attempted to dry lightgoods and heavy goods and goods of varying heat-absorbing capacity bysubjecting them to the direct or radiant action of a flame regulated asmentioned, and none of the devices known to me in which flame is applieddirectly to the goods are capable of adjustment or use so as toaccomplish this result. Another important difference between my methodand the prior art lies in the fact that I apply to a given mass ofmaterial in its wettest condition the direct or radiant action of aflame at its point of highest temperature in the receiver for a periodof time dependent upon the amount of moisture the goods contain and thengradually withdraw the material from the higher temperature and subjectit to a gradually-declining temperature as the amount of moisture in thegoods diminishes. Another important difference between my method and theprior art lies in the application of the highest temperature to thegreatest quantity of material in its wettest condition and thengradually reducing the quantity of material and the temperature of theair or gas to which it is exposed as the material becomes drier. Anotherimportant difference lies in the regulation of the temperature, force,and volume of the blast, so as to adjust it to the quantity and natureof the material to be treated. Another important difference lies in theprojection of a blast into the cylinder in a line substantially parallelto the axis of the cylinder and maintaining the force of the blast atthe point of inlet higher than at any other point in the cylinder.

Having thus described my invention, what Iclaim as new, and desire tosecure by Letters Patent of the United States, is

l. The combination in a drier of achamber, means forblowing orinjectingflame thereinto at one end through an opening of smaller diameter thanthat of the end of the chamber and located some distance above its base,means forsupplying to said end of the chamber material to be treated andmeans operating to advance the material progressively toward the otherend ofthe chamber, substantially as described.

2. The combination in a drier of a chamber, means for'blowingorinjeetingflame thereinto at one end through an opening of smaller diameter thanthat of the end of the chamber, and located at substantially the centerof said end, means for supplying to said end of the chamber material tobe treated, and means Operating to advancethe material progressivelytoward the other end of the chamber, substantially as described.

3. The combination in a drier of a chamber, means for blowing orinjecting flame thereinto at one end through an opening of smallerdiameter than that of the end of the chamber and located above thematerial to be treated, means for supplying to said end of the chambermaterial to be treated, and means operating to advance the materialprogressively toward the other end of the chamber, substantiallydescribed.

' i. A drier comprising a shell or drum, having its interior providedwith a series of shelves, the same increasing in number from the inletto the exit end of the drum, in combination with means for supplyingheat to the drum, substantially as described.

5. A drier comprising a shell or drum, having its interior provided witha series of shelves, the sanie increasing in num her from the inlet tothe exit end of the drum, substantially as described.

6. A drier comprising a shell or drum having its interior provided witha series of shelves, a dust-arrester arranged at the discharge end ofthe drum, comprising an openwork structure, and a brush carried by thedrum for removing accumulations from the interior walls of the saidarrester, substantially as described.

7. The combination with a chamber of a burner in communication with theinlet end thereof, an air-supply pipe in connection with the burner andprojecting beyond the same, substantially as described.

8. The combination with a revoluble drum, of a burner in communicationwith the inlet end thereof, an air-supply pipein connection with theburner, and projecting beyond the same, substantially as described.

9. A drier comprising a shell or drum having its interior provided witha series of shelves, a dust-arrester arranged at the discharge end ofthe drum, comprising an openwork structure, and a d ust-room inclosingthe dust-arrester, and provided with means for introducing cooler airwhereby to chill fine particles of material escaping thereto,substantially as described.

10. The combination with a revoluble drum of a stationary head-platecarrying a combustion-chamber, means for supplying a blast to the saidchamber, a burner arranged at the outer end of the said chamber, a fuel-supply pipe entering the combustion-chamber, and

means for regulating the supply of fuel to the burner, substantially asdescribed.

11. The combination in a drier of a chamber open atone end and closed atthe other, means for blowing flame into the closed end under pressure,and meansfor supplying to the chamber at the closed end material to bedried.

12. The combination in a drier of a chamber open at one end and closedat the other, means for blowing flame into the closed end under pressurein a direction substantially parallel to the line of discharge, andmeans of supplying to the chamber at the closed end material to bedried.

13. The combination in a drier of a chamber having adischarge-outlet,means for blowing flame partially therethrough from apas sage-Way alined with the line of discharge, means for supplying tothe said chamber material to be treated, and means operating to advancethe material through the chamber without burning, at a varied speeddependent upon the weight of the pieces.

14. The combination in a drier of a chamber having a discharge-outlet,means for forcing flame partially therethrough,in a line substantiallyparallel to the line of discharge, means for supplying such chamber withmaterial to be treated, and means operating to advance the materialthrough the chamber without burning, toward the outlet, at a speeddependent upon the heat-absorbing capacity of the material.

15. The combination in a drier, of a chamber closed at one end andhaving a dischargeoutlet at the other,an inlet through said closed endhaving substantially parallel Walls, and an area in cross-section lessthan that of the chamber, means for blowing flame into said chamberthrough said inlet, means for relieving the pressure at thedischarge-outlet and means for supplying to the chamber material to bedried. t

16. The combination in a drier, of a chamber provided with adischarge-outlet, a contracted inlet, of an area in cross-section lessthan that of the chamber, means for blowing the flame through said inletin a ,direction substantially parallel to the line of discharge, meansfor relieving the pressure at the discharge-outlet and means forsupplying to the chamber at or near the flame'inlet material to bedried.

17. The combination in a drier of a chamberhavinga discharge-outlet,means for blowing flame thereinto, in a direction substan tiallyparallel to the line of discharge, means for relieving the pressure atthe dischargeoutlet, and means for supplying to the chamber at, or nearthe fire-inlet, material to be dried, and means for agitating thematerial so as to bring it into the line of the blast.

18. The combination in a drier of a chamber having adischarge-outlet,means for blowing flame thereinto under pressure in adirection substantially parallel to the line of discharge, means forrelieving the pressure at the discharge-outlet, and means for supplyingto the chamber at, or near the fire-inlet, material to be dried, andmeans for subjecting the material intermittently to the action of theblast, first to the highest temperature, and subsequently to theconstantly-declining temperature.

19. The combination in a drier of a chamber havinga discharge-outlet,means for forcing flame partially therethrough in a line substantiallyparallel to the line of discharge, means for regulating and controllingthe temperature of the flame and force of the blast, means for supplyingto the said chamber ma terial to be treated, and means operating toadvance the material through the chamber without burning.

20. In a drier the combination of a cylinder, means for revolving thecylinder, means for projecting a flame under pressure into one end at orabout its center, and means for feeding to the cylinder'material to bedried, at the same end as the blast.

21. In a drier the combination of areceiver and agitator for the goods,said receiver be-- ing provided withadischarge-outlet,of means forfeeding material to be dried to the receiver always at substantially thesame point, and means for projecting a flame under pressure directlyoverthegoods in the direction of discharge, the point of maximumtemperature in the receiver being substantially opposite the point ofmaximum bulk of the goods.

22. In a drier the combination of a receiver having a discharge-outlet,means for agitating the goods in the receiver, means for feedingmaterial to be dried to the receiver, always at substantially the samepoint, and means for projecting a flame directly over the goods in thedirection of discharge, the point of maximum temperature in the receiverbeing opposite the point of maximum bulk of the goods.

23. In a drier the combination of a receiver having a discharge-outlet,means for agitating the goods, means for feeding material to be dried tothe receiver always at substantially the same point and means forprojecting a flame directly over the goods in the direction ofdischarge, so located that the point of maximum temperature in thereceiver will be opposite the maximum bulk of goods.

24. In a drier the combination of a receiver having a discharge-outlet,the means for feeding the material to be dried to the receiver at oneend, always at substantially the same point, whereby a maximum bulk ofgoods is maintained at the feed end, which gradually declines to thedischarge end, means for agitating all the goods to prevent burning, andmeans for projecting a blast over the goods,

the point of inlet of blast being over and opposite the maximum bulk ofgo0ds,and above the level of the discharging goods at the discharge end.

25. In adrier the combination of a receiver having a discharge-outlet,embodying a receiving-bed, having a rear wall forming an abrupt anglewith the bed, with means for feeding material to be dried to the bed,immediately in front of the abrupt wall, means for agitating all thegoods on the receivingbed, and means for blowing a blast over the goods,the point of inlet of blast being opposite to the point of maximum bulkof goods, and above the level of the discharging goods at the dischargeend.

26. In adrier the combination of a receiver, means for projecting ablast thereinto, means for regulating and controlling the force, volumeand temperature of the blast to produce a desired power, means foradvancing the material to be dried through the chamber, and means forsupplying to the receiver material to be dried, and acted upon by theblast so as substantially to balance the power and work at all points inthe receiver.

27. In a drier the combination of a receiver, means for projecting aflame thereinto under pressure, means for regulating and controlling theforce, volume and temperature of the blast, to produce the desiredpower, means for advancing the material to be dried through the chamber,and means for supplying to the receiver material to be dried, andregulating the volume of material fed to the receiver, and acted upon bythe blast so as substantially to balance the power and work at allpoints in the receiver, substantially as described.

28. In a drier the combination of a receiver, means for projecting ablast thereinto, means for regulating and controlling the pressure,volume and temperature of the blast to produce a desired power, andmeans for supplying to the receiver material to be dried in regulatedquantity, so as to present to the power at all points in the receiver anamount of work proportional thereto.

29. In adrier the combination of aninclined rotating drum, open at oneend and closed at the other by a stationary Wall, means for projecting aflame through said wall into said drum at a substantial distance abovethe base of said drum, means for feeding material to be dried into saiddrum through said wall, and means for rotating said drum.

In testimony whereof I affix my signature in presence of two witnesses.

ABRAHAM T. l/VELOH.

"Witnesses:

E. T. BRANDENBURG, R. M. ELLIOTT.

